Piston type fluid brake



Oct. 1951 J. c. FOSTER, sR., ETAL ,5 9,712

PISTON TYPE FLUID BRAKE Filed July 14, 1949 2 Sheets-Sheet 1 115992-9 5, JClfasZ'sagv/r ATTOR NEY;

715 .JCfl'ZaZeqEr,

Oct. 2, 1951 c FOSTER, 5 r I 2,569,712

PISTON TYPE FLUID BRAKE 2 Sheets-Sheet 2 3 l9 Filed July 14, 1949 JHB i995; BY

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ATTOR N E151 Patented Oct. 2, 1951 1.?ATENT QFFICE John 0. Foster, $17., John Henry Biggs, and

JohnG: Foster, In, Qdessa, Tex.

Annli aticn J ly 14, 1949-, s ria N6. 1 4 162 4; Ch me- 1' y i This invention relates to fluid or hydraulic rakes a d. is an im a sali nt er the en i fi eh: em ed ed 1? an 31 99;? 51 Mmnaa 1 n An; Object of. this invention is to provide an in provedjbralge of the fluid type whereby otation of; a Shaft may be. braked} the braking, force. ein regulated bimea i a in le e lating valve.

Another object ofthis invention is to prov e a f ui ra where n he ma m r k g i res is. less than a positive lockingof the device so ha th r vi shaft W 1 me om le y locked,

A further object of thisinvention is to provide a fluid brake embodying a minimum of parts so that the device can be made strong enough to withstand strains; pplied thereto, and can be made n e ai qv l 11 With theabove and other objects in view, our invention consists in the arrangement, combination and details of construction disclosed in the drawings and specification, and then'moiepan ticularly pointed out in the appended claims.

In e drawin s Figure. l is a detail end elevation of a hydraulic brake constructed according to an embodimentnf our invention, showing, one end plate'removed therefrom, v

Figure 2" isa sectional view taken on the, line 2"2"of"Figure1,'

Figure 3 is a sectional view taken on the line 3--3 of Figure 2,

Figure 4 is a fragmentary sectional view taken on the line 4-4 of Figure 1,

Figure 5 is a fragmentary sectional view taken on the line 5-5 of Figure 2.

Referring to the drawings, the numeral l0 designates generally a stationary housing which has secured thereto end plates II and [2. The housing II is provided with a centrally disposed chamber l3 and a shaft [4 is journalled centrally through the end members II and I2. Packing glands l5 and I6 seal the shaft M with respect to the end members H and I2.

The housing I!) is formed With a plurality of radially disposed cylinders l1, and cylinder liners P8 are removably disposed in each cylinder 11, being provided at their outer ends with aimular flanges IS.

A screw plug 2|] is threaded into the outer end of each cylinder H for sealing the open outer end of each cylinder and for holding the lining P8 in the cylinder l1. There is a piston 2| slidable in each lining l8 which has a connecting rod 22 piv- 2 otally connected with the inner end thereof; and t om e'cua jma 22 engages a circular cam' 23 ichi's fixedonthefshaft M. The cylinders l'T arearranged in diametrically opposed pairs and 5 preferably, as shown in Figure 2, the pairs of cylindersfar offsetone pair to the-adjacentpair.

The housing This provided with a plurality of radiail "disposed ducts or ports'z ijwhi'ch commanic e at their inner ends with the central l3; andthe housing or body 10, is also with connecting passages 25' which conradial passages or ports 24 with the outer one of the cylinders 11'. A bypassiorbleeder gle Z5 is formed in the body H! between radial *4. arid cylinder ll'and'a sshown in Figure 2,

ofjpistonzl is formed with a bleeder 21; The; port 21; isjdisposed in registrywith ble jr passage 26' when piston 21 is at, the inner 11i 11$ mQ QmIi a d mso er w n e piston; lf'moves outwardly aftera slight outward merit of piston 2 L "The operation of passages 26 and 21 is that of a by-passor a bleeder operationto relieve pressure developed in passage; 24 as the skirt aperture 21 registerswith passage 26 to allow the piston to complete its movement toward the top of the cylinder. The skirt of the-piston covers passage 2:6. during part of the lip-stroke but isso designed that the interconnecting passages and the dimensions and'position of passage 26 effect braking of maximum efficiency.

An annular valve member 29 is rotatably disposed in the chamber 13, being formed with a plurality of ports 30 adapted to be disposed in registry with ports 24, and valve member 29 is formed at its outer end with an annular flange 3|. A retainer ring 32 is secured to the inner end of valve member 29 for holding the valve member 29 against endwise movement while permitting free circumferential movement or adjustment thereof. The valve member 29 has secured to the flange 3| thereof, as shown in Figure 1, a fragmentary gear member 32 which meshes with a circular adjusting gear 33. The gear 33 is mounted on a shaft 34 which is jour nailed through the end or head [2 and is provided on its outer end with a handle or lever 35 by means of which the shaft 34 and the gear 33 may be rotatably adjusted to provide for regulation of the opening or closing of ports 24.

In the use and operation of this device, the housing ii! is fixed to a suitable stationary element, and the shaft I4 is connected with a suitable rotating means which may be a vehicle axle, a driving shaft or other suitable means. When of positioning of ports 30 out of registry with I ports 24 will determine the effective braking force applied to the movement of pistons 2| which in turn will apply a braking force to the rotation.

of shaft I4.

We do not mean to confine ourselves to the exact details of construction herein-disclosed, but claim all variations falling within the purview of H the appended claims.

What we claim is: l 1. A fluid brake comprising a stationary housing, a shaft journalled through said housing, said housing being formed with a, plurality of radially disposed cylinders, pistons slidable in said cylinders having apertured skirt portions, means connecting said pistons with said shaft for reciprocation of said pistons, said housing being formed with a chamber about said shaft and also formed with passages communicating the outer end portions of said cylinders with said chamber, transverse passages communicating with said outer end portions and with inner end portions of said cylinders for registry with said apertured skirt on movement of the piston thereof past a given point, an annular valve member rotatably carried by said housing formed with ports adapted for registry with said passages, and means for adjusting said valve member to regulate a partial flow of fluid from said cylinders to said chamber. 7 2. A fluid brake comprising a stationary housing, a shaft journalled through said housing, said housing being formed with a plurality of radially disposed cylinders, pistons slidable in said cylinders, means connecting said pistons with said shaft for reciprocation of said pistons, said housing being formed with a chamber about said shaft and also formed with passages communicating the outer end portions of said cylinders with said chamber, an annular valve member rotatably carried by said housing formed with ports adapted 4 for registry with said passages, and means for adjusting said valve member to regulate the flow of fluid from said cylinders to said chamber, said housing also having bleeder passages communicating said first named passages with the inner portions of said cylinders.

3. A fluid brake comprising a stationary body formed with a central fluid chamber and a plurality of radially arranged cylinders, a shaft journalled through said chamber, eccentrics fixed to said shaft, pistons slidable in said cylinders having skirt'portions, an aperture formed in each of said skirt portions spaced intermediate thereof, connecting rods connecting said pistons with said eccentrics, said body having radially disposed passages communicating the outer portions of each cylinder with said chamber, a ring-shaped valve member rotatably carried by said body and formed with ports adapted for registry with said passages, lever. means for rotating said valve member.

i 4. A fluid brake comprising a stationary body formed with a central fluid chamber and a plurality of radially arranged cylinders, a shaft journalled through said chamber, eccentrics flxed to said shaft, pistons slidable in said cylinders, connecting rods connecting said pistons with said eccentrics, said body having radially disposed passages communicating the outer portions of each cylinder with said chamber, said body having bleeder passages communicating said first named passages with the inner portions of said cylinders, a ring-shaped valve member rotatably carried by said body and formed with ports adapted for registry with said passages, and means for rotating said valve member.

JOHN C. FOSTER, SR. JOHN HENRY BIGGS. JOHNC. FOSTER, JR.

REFERENCES CITED The following references are of record in the file of this patent:

v UNITED STATES PATENTS Number Name Date 1,476,170 Morlan Dec. 4, 1923 1,480,194 Bixler et a1. Jan. 8, 1924 1,978,742 Drake Oct. 30, 1934 2,277,096 Foster et a1. Mar. 24, 1942 

